Ubuntu Manpage: Config::Model::models::Systemd::Section::Service

Provided by: libconfig-model-systemd-perl_0.236.1-1_all

NAME

       Config::Model::models::Systemd::Section::Service - Configuration class
       Systemd::Section::Service

DESCRIPTION

Configuration classes used by Config::Model

A unit configuration file whose name ends in .service encodes information about a process
controlled and supervised by systemd.

This man page lists the configuration options specific to this unit type. See
systemd.unit(5) for the common options of all unit configuration files. The common
configuration items are configured in the generic "[Unit]" and "[Install]" sections. The
service specific configuration options are configured in the "[Service]" section.

Additional options are listed in systemd.exec(5), which define the execution environment
the commands are executed in, and in systemd.kill(5), which define the way the processes
of the service are terminated, and in systemd.resource-control(5), which configure
resource control settings for the processes of the service.

If a service is requested under a certain name but no unit configuration file is found,
systemd looks for a SysV init script by the same name (with the .service suffix removed)
and dynamically creates a service unit from that script. This is useful for compatibility
with SysV. Note that this compatibility is quite comprehensive but not 100%. For details
about the incompatibilities, see the Incompatibilities with SysV document. This
configuration class was generated from systemd documentation. by parse-man.pl
<https://github.com/dod38fr/config-model-systemd/contrib/parse-man.pl>

Elements

CPUAccounting
Turn on CPU usage accounting for this unit. Takes a boolean argument. Note that turning on
CPU accounting for one unit will also implicitly turn it on for all units contained in the
same slice and for all its parent slices and the units contained therein. The system
default for this setting may be controlled with "DefaultCPUAccounting" in
systemd-system.conf(5). Optional. Type boolean.

CPUWeight
Assign the specified CPU time weight to the processes executed, if the unified control
group hierarchy is used on the system. These options take an integer value and control the
"cpu.weight" control group attribute. The allowed range is 1 to 10000. Defaults to 100.
For details about this control group attribute, see cgroup-v2.txt and
sched-design-CFS.txt. The available CPU time is split up among all units within one slice
relative to their CPU time weight.

While "StartupCPUWeight" only applies to the startup phase of the system, "CPUWeight"
applies to normal runtime of the system, and if the former is not set also to the startup
phase. Using "StartupCPUWeight" allows prioritizing specific services at boot-up
differently than during normal runtime.

Implies "CPUAccounting=true".

These settings replace "CPUShares" and "StartupCPUShares". Optional. Type integer.

upstream_default value :
100

StartupCPUWeight
Assign the specified CPU time weight to the processes executed, if the unified control
group hierarchy is used on the system. These options take an integer value and control the
"cpu.weight" control group attribute. The allowed range is 1 to 10000. Defaults to 100.
For details about this control group attribute, see cgroup-v2.txt and
sched-design-CFS.txt. The available CPU time is split up among all units within one slice
relative to their CPU time weight.

Implies "CPUAccounting=true".

These settings replace "CPUShares" and "StartupCPUShares". Optional. Type integer.

upstream_default value :
100

CPUQuota
Assign the specified CPU time quota to the processes executed. Takes a percentage value,
suffixed with "%". The percentage specifies how much CPU time the unit shall get at
maximum, relative to the total CPU time available on one CPU. Use values > 100% for
allotting CPU time on more than one CPU. This controls the "cpu.max" attribute on the
unified control group hierarchy and "cpu.cfs_quota_us" on legacy. For details about these
control group attributes, see cgroup-v2.txt and sched-design-CFS.txt.

Example: "CPUQuota=20%" ensures that the executed processes will never get more than 20%
CPU time on one CPU.

Implies "CPUAccounting=true". Optional. Type uniline.

MemoryAccounting
Turn on process and kernel memory accounting for this unit. Takes a boolean argument. Note
that turning on memory accounting for one unit will also implicitly turn it on for all
units contained in the same slice and for all its parent slices and the units contained
therein. The system default for this setting may be controlled with
"DefaultMemoryAccounting" in systemd-system.conf(5). Optional. Type boolean.

MemoryLow
Specify the best-effort memory usage protection of the executed processes in this unit. If
the memory usages of this unit and all its ancestors are below their low boundaries, this
unit's memory won't be reclaimed as long as memory can be reclaimed from unprotected
units.

Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified
memory size is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base
1024), respectively. Alternatively, a percentage value may be specified, which is taken
relative to the installed physical memory on the system. This controls the "memory.low"
control group attribute. For details about this control group attribute, see
cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting is supported only if the unified control group hierarchy is used and disables
"MemoryLimit". Optional. Type uniline.

MemoryHigh
Specify the high limit on memory usage of the executed processes in this unit. Memory
usage may go above the limit if unavoidable, but the processes are heavily slowed down and
memory is taken away aggressively in such cases. This is the main mechanism to control
memory usage of a unit.

Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified
memory size is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base
1024), respectively. Alternatively, a percentage value may be specified, which is taken
relative to the installed physical memory on the system. If assigned the special value
"infinity", no memory limit is applied. This controls the "memory.high" control group
attribute. For details about this control group attribute, see cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting is supported only if the unified control group hierarchy is used and disables
"MemoryLimit". Optional. Type uniline.

MemoryMax
Specify the absolute limit on memory usage of the executed processes in this unit. If
memory usage cannot be contained under the limit, out-of-memory killer is invoked inside
the unit. It is recommended to use "MemoryHigh" as the main control mechanism and use
"MemoryMax" as the last line of defense.

Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified
memory size is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base
1024), respectively. Alternatively, a percentage value may be specified, which is taken
relative to the installed physical memory on the system. If assigned the special value
"infinity", no memory limit is applied. This controls the "memory.max" control group
attribute. For details about this control group attribute, see cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting replaces "MemoryLimit". Optional. Type uniline.

MemorySwapMax
Specify the absolute limit on swap usage of the executed processes in this unit.

Takes a swap size in bytes. If the value is suffixed with K, M, G or T, the specified swap
size is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024),
respectively. If assigned the special value "infinity", no swap limit is applied. This
controls the "memory.swap.max" control group attribute. For details about this control
group attribute, see cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting is supported only if the unified control group hierarchy is used and disables
"MemoryLimit". Optional. Type uniline.

TasksAccounting
Turn on task accounting for this unit. Takes a boolean argument. If enabled, the system
manager will keep track of the number of tasks in the unit. The number of tasks accounted
this way includes both kernel threads and userspace processes, with each thread counting
individually. Note that turning on tasks accounting for one unit will also implicitly turn
it on for all units contained in the same slice and for all its parent slices and the
units contained therein. The system default for this setting may be controlled with
"DefaultTasksAccounting" in systemd-system.conf(5). Optional. Type boolean.

TasksMax
Specify the maximum number of tasks that may be created in the unit. This ensures that the
number of tasks accounted for the unit (see above) stays below a specific limit. This
either takes an absolute number of tasks or a percentage value that is taken relative to
the configured maximum number of tasks on the system. If assigned the special value
"infinity", no tasks limit is applied. This controls the "pids.max" control group
attribute. For details about this control group attribute, see pids.txt.

Implies "TasksAccounting=true". The system default for this setting may be controlled with
"DefaultTasksMax" in systemd-system.conf(5). Optional. Type uniline.

IOAccounting
Turn on Block I/O accounting for this unit, if the unified control group hierarchy is used
on the system. Takes a boolean argument. Note that turning on block I/O accounting for one
unit will also implicitly turn it on for all units contained in the same slice and all for
its parent slices and the units contained therein. The system default for this setting may
be controlled with "DefaultIOAccounting" in systemd-system.conf(5).

This setting replaces "BlockIOAccounting" and disables settings prefixed with "BlockIO" or
"StartupBlockIO". Optional. Type boolean.

IOWeight
Set the default overall block I/O weight for the executed processes, if the unified
control group hierarchy is used on the system. Takes a single weight value (between 1 and
10000) to set the default block I/O weight. This controls the "io.weight" control group
attribute, which defaults to 100. For details about this control group attribute, see
cgroup-v2.txt. The available I/O bandwidth is split up among all units within one slice
relative to their block I/O weight.

While "StartupIOWeight" only applies to the startup phase of the system, "IOWeight"
applies to the later runtime of the system, and if the former is not set also to the
startup phase. This allows prioritizing specific services at boot-up differently than
during runtime.

Implies "IOAccounting=true".

These settings replace "BlockIOWeight" and "StartupBlockIOWeight" and disable settings
prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

StartupIOWeight
Set the default overall block I/O weight for the executed processes, if the unified
control group hierarchy is used on the system. Takes a single weight value (between 1 and
10000) to set the default block I/O weight. This controls the "io.weight" control group
attribute, which defaults to 100. For details about this control group attribute, see
cgroup-v2.txt. The available I/O bandwidth is split up among all units within one slice
relative to their block I/O weight.

Implies "IOAccounting=true".

These settings replace "BlockIOWeight" and "StartupBlockIOWeight" and disable settings
prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IODeviceWeight
Set the per-device overall block I/O weight for the executed processes, if the unified
control group hierarchy is used on the system. Takes a space-separated pair of a file path
and a weight value to specify the device specific weight value, between 1 and 10000.
(Example: "/dev/sda 1000"). The file path may be specified as path to a block device node
or as any other file, in which case the backing block device of the file system of the
file is determined. This controls the "io.weight" control group attribute, which defaults
to 100. Use this option multiple times to set weights for multiple devices. For details
about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

This setting replaces "BlockIODeviceWeight" and disables settings prefixed with "BlockIO"
or "StartupBlockIO". Optional. Type uniline.

IOReadBandwidthMax
Set the per-device overall block I/O bandwidth maximum limit for the executed processes,
if the unified control group hierarchy is used on the system. This limit is not work-
conserving and the executed processes are not allowed to use more even if the device has
idle capacity. Takes a space-separated pair of a file path and a bandwidth value (in
bytes per second) to specify the device specific bandwidth. The file path may be a path to
a block device node, or as any other file in which case the backing block device of the
file system of the file is used. If the bandwidth is suffixed with K, M, G, or T, the
specified bandwidth is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes,
respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the "io.max" control
group attributes. Use this option multiple times to set bandwidth limits for multiple
devices. For details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings replace "BlockIOReadBandwidth" and "BlockIOWriteBandwidth" and disable
settings prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IOWriteBandwidthMax
Set the per-device overall block I/O bandwidth maximum limit for the executed processes,
if the unified control group hierarchy is used on the system. This limit is not work-
conserving and the executed processes are not allowed to use more even if the device has
idle capacity. Takes a space-separated pair of a file path and a bandwidth value (in
bytes per second) to specify the device specific bandwidth. The file path may be a path to
a block device node, or as any other file in which case the backing block device of the
file system of the file is used. If the bandwidth is suffixed with K, M, G, or T, the
specified bandwidth is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes,
respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the "io.max" control
group attributes. Use this option multiple times to set bandwidth limits for multiple
devices. For details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings replace "BlockIOReadBandwidth" and "BlockIOWriteBandwidth" and disable
settings prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IOReadIOPSMax
Set the per-device overall block I/O IOs-Per-Second maximum limit for the executed
processes, if the unified control group hierarchy is used on the system. This limit is not
work-conserving and the executed processes are not allowed to use more even if the device
has idle capacity. Takes a space-separated pair of a file path and an IOPS value to
specify the device specific IOPS. The file path may be a path to a block device node, or
as any other file in which case the backing block device of the file system of the file is
used. If the IOPS is suffixed with K, M, G, or T, the specified IOPS is parsed as
KiloIOPS, MegaIOPS, GigaIOPS, or TeraIOPS, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 1K"). This controls the "io.max" control
group attributes. Use this option multiple times to set IOPS limits for multiple devices.
For details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings are supported only if the unified control group hierarchy is used and
disable settings prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IOWriteIOPSMax
Set the per-device overall block I/O IOs-Per-Second maximum limit for the executed
processes, if the unified control group hierarchy is used on the system. This limit is not
work-conserving and the executed processes are not allowed to use more even if the device
has idle capacity. Takes a space-separated pair of a file path and an IOPS value to
specify the device specific IOPS. The file path may be a path to a block device node, or
as any other file in which case the backing block device of the file system of the file is
used. If the IOPS is suffixed with K, M, G, or T, the specified IOPS is parsed as
KiloIOPS, MegaIOPS, GigaIOPS, or TeraIOPS, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 1K"). This controls the "io.max" control
group attributes. Use this option multiple times to set IOPS limits for multiple devices.
For details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings are supported only if the unified control group hierarchy is used and
disable settings prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IPAccounting
Takes a boolean argument. If true, turns on IPv4 and IPv6 network traffic accounting for
packets sent or received by the unit. When this option is turned on, all IPv4 and IPv6
sockets created by any process of the unit are accounted for. When this option is used in
socket units, it applies to all IPv4 and IPv6 sockets associated with it (including both
listening and connection sockets where this applies). Note that for socket-activated
services, this configuration setting and the accounting data of the service unit and the
socket unit are kept separate, and displayed separately. No propagation of the setting and
the collected statistics is done, in either direction. Moreover, any traffic sent or
received on any of the socket unit's sockets is accounted to the socket unit X and never
to the service unit it might have activated, even if the socket is used by it. Note that
IP accounting is currently not supported for slice units, and enabling this option for
them has no effect. The system default for this setting may be controlled with
"DefaultIPAccounting" in systemd-system.conf(5). Optional. Type boolean.

IPAddressAllow
Turn on address range network traffic filtering for packets sent and received over AF_INET
and AF_INET6 sockets. Both directives take a space separated list of IPv4 or IPv6
addresses, each optionally suffixed with an address prefix length (separated by a "/"
character). If the latter is omitted, the address is considered a host address, i.e. the
prefix covers the whole address (32 for IPv4, 128 for IPv6).

The access lists configured with this option are applied to all sockets created by
processes of this unit (or in the case of socket units, associated with it). The lists are
implicitly combined with any lists configured for any of the parent slice units this unit
might be a member of. By default all access lists are empty. When configured the lists are
enforced as follows:

In order to implement a whitelisting IP firewall, it is recommended to use a
"IPAddressDeny""any" setting on an upper-level slice unit (such as the root slice -.slice
or the slice containing all system services system.slice X see systemd.special(7) for
details on these slice units), plus individual per-service "IPAddressAllow" lines
permitting network access to relevant services, and only them.

Note that for socket-activated services, the IP access list configured on the socket unit
applies to all sockets associated with it directly, but not to any sockets created by the
ultimately activated services for it. Conversely, the IP access list configured for the
service is not applied to any sockets passed into the service via socket activation. Thus,
it is usually a good idea, to replicate the IP access lists on both the socket and the
service unit, however it often makes sense to maintain one list more open and the other
one more restricted, depending on the usecase.

If these settings are used multiple times in the same unit the specified lists are
combined. If an empty string is assigned to these settings the specific access list is
reset and all previous settings undone.

In place of explicit IPv4 or IPv6 address and prefix length specifications a small set of
symbolic names may be used. The following names are defined:

Note that these settings might not be supported on some systems (for example if eBPF
control group support is not enabled in the underlying kernel or container manager). These
settings will have no effect in that case. If compatibility with such systems is desired
it is hence recommended to not exclusively rely on them for IP security. Optional. Type
uniline.

IPAddressDeny
Turn on address range network traffic filtering for packets sent and received over AF_INET
and AF_INET6 sockets. Both directives take a space separated list of IPv4 or IPv6
addresses, each optionally suffixed with an address prefix length (separated by a "/"
character). If the latter is omitted, the address is considered a host address, i.e. the
prefix covers the whole address (32 for IPv4, 128 for IPv6).

In place of explicit IPv4 or IPv6 address and prefix length specifications a small set of
symbolic names may be used. The following names are defined:

DeviceAllow
Control access to specific device nodes by the executed processes. Takes two space-
separated strings: a device node specifier followed by a combination of "r", "w", "m" to
control reading, writing, or creation of the specific device node(s) by the unit (mknod),
respectively. This controls the "devices.allow" and "devices.deny" control group
attributes. For details about these control group attributes, see devices.txt.

The device node specifier is either a path to a device node in the file system, starting
with /dev/, or a string starting with either "char-" or "block-" followed by a device
group name, as listed in /proc/devices. The latter is useful to whitelist all current and
future devices belonging to a specific device group at once. The device group is matched
according to filename globbing rules, you may hence use the "*" and "?" wildcards.
Examples: /dev/sda5 is a path to a device node, referring to an ATA or SCSI block device.
"char-pts" and "char-alsa" are specifiers for all pseudo TTYs and all ALSA sound devices,
respectively. "char-cpu/*" is a specifier matching all CPU related device groups.
Optional. Type list of uniline.

DevicePolicy
Control the policy for allowing device access: Optional. Type enum. choice: 'auto',
'closed', 'strict'.

Slice
The name of the slice unit to place the unit in. Defaults to system.slice for all non-
instantiated units of all unit types (except for slice units themselves see below).
Instance units are by default placed in a subslice of system.slice that is named after the
template name.

This option may be used to arrange systemd units in a hierarchy of slices each of which
might have resource settings applied.

For units of type slice, the only accepted value for this setting is the parent slice.
Since the name of a slice unit implies the parent slice, it is hence redundant to ever set
this parameter directly for slice units.

Special care should be taken when relying on the default slice assignment in templated
service units that have "DefaultDependencies=no" set, see systemd.service(5), section
"Default Dependencies" for details. Optional. Type uniline.

Delegate
Turns on delegation of further resource control partitioning to processes of the unit.
Units where this is enabled may create and manage their own private subhierarchy of
control groups below the control group of the unit itself. For unprivileged services (i.e.
those using the "User" setting) the unit's control group will be made accessible to the
relevant user. When enabled the service manager will refrain from manipulating control
groups or moving processes below the unit's control group, so that a clear concept of
ownership is established: the control group tree above the unit's control group (i.e.
towards the root control group) is owned and managed by the service manager of the host,
while the control group tree below the unit's control group is owned and managed by the
unit itself. Takes either a boolean argument or a list of control group controller names.
If true, delegation is turned on, and all supported controllers are enabled for the unit,
making them available to the unit's processes for management. If false, delegation is
turned off entirely (and no additional controllers are enabled). If set to a list of
controllers, delegation is turned on, and the specified controllers are enabled for the
unit. Note that additional controllers than the ones specified might be made available as
well, depending on configuration of the containing slice unit or other units contained in
it. Note that assigning the empty string will enable delegation, but reset the list of
controllers, all assignments prior to this will have no effect. Defaults to false.

Note that controller delegation to less privileged code is only safe on the unified
control group hierarchy. Accordingly, access to the specified controllers will not be
granted to unprivileged services on the legacy hierarchy, even when requested.

The following controller names may be specified: "cpu", "cpuacct", "io", "blkio",
"memory", "devices", "pids". Not all of these controllers are available on all kernels
however, and some are specific to the unified hierarchy while others are specific to the
legacy hierarchy. Also note that the kernel might support further controllers, which
aren't covered here yet as delegation is either not supported at all for them or not
defined cleanly. Optional. Type uniline.

CPUShares
Assign the specified CPU time share weight to the processes executed. These options take
an integer value and control the "cpu.shares" control group attribute. The allowed range
is 2 to 262144. Defaults to 1024. For details about this control group attribute, see
sched-design-CFS.txt. The available CPU time is split up among all units within one slice
relative to their CPU time share weight.

While "StartupCPUShares" only applies to the startup phase of the system, "CPUShares"
applies to normal runtime of the system, and if the former is not set also to the startup
phase. Using "StartupCPUShares" allows prioritizing specific services at boot-up
differently than during normal runtime.

Implies "CPUAccounting=true".

These settings are deprecated. Use "CPUWeight" and "StartupCPUWeight" instead. Optional.
Type integer.

upstream_default value :
1024

StartupCPUShares
Assign the specified CPU time share weight to the processes executed. These options take
an integer value and control the "cpu.shares" control group attribute. The allowed range
is 2 to 262144. Defaults to 1024. For details about this control group attribute, see
sched-design-CFS.txt. The available CPU time is split up among all units within one slice
relative to their CPU time share weight.

Implies "CPUAccounting=true".

These settings are deprecated. Use "CPUWeight" and "StartupCPUWeight" instead. Optional.
Type integer.

upstream_default value :
1024

MemoryLimit
Specify the limit on maximum memory usage of the executed processes. The limit specifies
how much process and kernel memory can be used by tasks in this unit. Takes a memory size
in bytes. If the value is suffixed with K, M, G or T, the specified memory size is parsed
as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively.
Alternatively, a percentage value may be specified, which is taken relative to the
installed physical memory on the system. If assigned the special value "infinity", no
memory limit is applied. This controls the "memory.limit_in_bytes" control group
attribute. For details about this control group attribute, see memory.txt.

Implies "MemoryAccounting=true".

This setting is deprecated. Use "MemoryMax" instead. Optional. Type uniline.

BlockIOAccounting
Turn on Block I/O accounting for this unit, if the legacy control group hierarchy is used
on the system. Takes a boolean argument. Note that turning on block I/O accounting for one
unit will also implicitly turn it on for all units contained in the same slice and all for
its parent slices and the units contained therein. The system default for this setting may
be controlled with "DefaultBlockIOAccounting" in systemd-system.conf(5).

This setting is deprecated. Use "IOAccounting" instead. Optional. Type boolean.

BlockIOWeight
Set the default overall block I/O weight for the executed processes, if the legacy control
group hierarchy is used on the system. Takes a single weight value (between 10 and 1000)
to set the default block I/O weight. This controls the "blkio.weight" control group
attribute, which defaults to 500. For details about this control group attribute, see
blkio-controller.txt. The available I/O bandwidth is split up among all units within one
slice relative to their block I/O weight.

While "StartupBlockIOWeight" only applies to the startup phase of the system,
"BlockIOWeight" applies to the later runtime of the system, and if the former is not set
also to the startup phase. This allows prioritizing specific services at boot-up
differently than during runtime.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOWeight" and "StartupIOWeight" instead. Optional.
Type uniline.

StartupBlockIOWeight
Set the default overall block I/O weight for the executed processes, if the legacy control
group hierarchy is used on the system. Takes a single weight value (between 10 and 1000)
to set the default block I/O weight. This controls the "blkio.weight" control group
attribute, which defaults to 500. For details about this control group attribute, see
blkio-controller.txt. The available I/O bandwidth is split up among all units within one
slice relative to their block I/O weight.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOWeight" and "StartupIOWeight" instead. Optional.
Type uniline.

BlockIODeviceWeight
Set the per-device overall block I/O weight for the executed processes, if the legacy
control group hierarchy is used on the system. Takes a space-separated pair of a file path
and a weight value to specify the device specific weight value, between 10 and 1000.
(Example: "/dev/sda 500"). The file path may be specified as path to a block device node
or as any other file, in which case the backing block device of the file system of the
file is determined. This controls the "blkio.weight_device" control group attribute, which
defaults to 1000. Use this option multiple times to set weights for multiple devices. For
details about this control group attribute, see blkio-controller.txt.

Implies "BlockIOAccounting=true".

This setting is deprecated. Use "IODeviceWeight" instead. Optional. Type uniline.

BlockIOReadBandwidth
Set the per-device overall block I/O bandwidth limit for the executed processes, if the
legacy control group hierarchy is used on the system. Takes a space-separated pair of a
file path and a bandwidth value (in bytes per second) to specify the device specific
bandwidth. The file path may be a path to a block device node, or as any other file in
which case the backing block device of the file system of the file is used. If the
bandwidth is suffixed with K, M, G, or T, the specified bandwidth is parsed as Kilobytes,
Megabytes, Gigabytes, or Terabytes, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the
"blkio.throttle.read_bps_device" and "blkio.throttle.write_bps_device" control group
attributes. Use this option multiple times to set bandwidth limits for multiple devices.
For details about these control group attributes, see blkio-controller.txt.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOReadBandwidthMax" and "IOWriteBandwidthMax" instead.
Optional. Type uniline.

BlockIOWriteBandwidth
Set the per-device overall block I/O bandwidth limit for the executed processes, if the
legacy control group hierarchy is used on the system. Takes a space-separated pair of a
file path and a bandwidth value (in bytes per second) to specify the device specific
bandwidth. The file path may be a path to a block device node, or as any other file in
which case the backing block device of the file system of the file is used. If the
bandwidth is suffixed with K, M, G, or T, the specified bandwidth is parsed as Kilobytes,
Megabytes, Gigabytes, or Terabytes, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the
"blkio.throttle.read_bps_device" and "blkio.throttle.write_bps_device" control group
attributes. Use this option multiple times to set bandwidth limits for multiple devices.
For details about these control group attributes, see blkio-controller.txt.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOReadBandwidthMax" and "IOWriteBandwidthMax" instead.
Optional. Type uniline.

WorkingDirectory
Takes a directory path relative to the service's root directory specified by
"RootDirectory", or the special value "~". Sets the working directory for executed
processes. If set to "~", the home directory of the user specified in "User" is used. If
not set, defaults to the root directory when systemd is running as a system instance and
the respective user's home directory if run as user. If the setting is prefixed with the
"-" character, a missing working directory is not considered fatal. If
"RootDirectory"/"RootImage" is not set, then "WorkingDirectory" is relative to the root of
the system running the service manager. Note that setting this parameter might result in
additional dependencies to be added to the unit (see above). Optional. Type uniline.

RootDirectory
Takes a directory path relative to the host's root directory (i.e. the root of the system
running the service manager). Sets the root directory for executed processes, with the
chroot(2) system call. If this is used, it must be ensured that the process binary and all
its auxiliary files are available in the chroot() jail. Note that setting this parameter
might result in additional dependencies to be added to the unit (see above).

The "MountAPIVFS" and "PrivateUsers" settings are particularly useful in conjunction with
"RootDirectory". For details, see below. Optional. Type uniline.

RootImage
Takes a path to a block device node or regular file as argument. This call is similar to
"RootDirectory" however mounts a file system hierarchy from a block device node or
loopback file instead of a directory. The device node or file system image file needs to
contain a file system without a partition table, or a file system within an MBR/MS-DOS or
GPT partition table with only a single Linux-compatible partition, or a set of file
systems within a GPT partition table that follows the Discoverable Partitions
Specification. Optional. Type uniline.

MountAPIVFS
Takes a boolean argument. If on, a private mount namespace for the unit's processes is
created and the API file systems /proc, /sys, and /dev are mounted inside of it, unless
they are already mounted. Note that this option has no effect unless used in conjunction
with "RootDirectory"/"RootImage" as these three mounts are generally mounted in the host
anyway, and unless the root directory is changed, the private mount namespace will be a
1:1 copy of the host's, and include these three mounts. Note that the /dev file system of
the host is bind mounted if this option is used without "PrivateDevices". To run the
service with a private, minimal version of /dev/, combine this option with
"PrivateDevices". Optional. Type boolean.

BindPaths
Configures unit-specific bind mounts. A bind mount makes a particular file or directory
available at an additional place in the unit's view of the file system. Any bind mounts
created with this option are specific to the unit, and are not visible in the host's mount
table. This option expects a whitespace separated list of bind mount definitions. Each
definition consists of a colon-separated triple of source path, destination path and
option string, where the latter two are optional. If only a source path is specified the
source and destination is taken to be the same. The option string may be either "rbind" or
"norbind" for configuring a recursive or non-recursive bind mount. If the destination path
is omitted, the option string must be omitted too.

"BindPaths" creates regular writable bind mounts (unless the source file system mount is
already marked read-only), while "BindReadOnlyPaths" creates read-only bind mounts. These
settings may be used more than once, each usage appends to the unit's list of bind mounts.
If the empty string is assigned to either of these two options the entire list of bind
mounts defined prior to this is reset. Note that in this case both read-only and regular
bind mounts are reset, regardless which of the two settings is used.

This option is particularly useful when "RootDirectory"/"RootImage" is used. In this case
the source path refers to a path on the host file system, while the destination path
refers to a path below the root directory of the unit. Optional. Type list of uniline.

BindReadOnlyPaths
Configures unit-specific bind mounts. A bind mount makes a particular file or directory
available at an additional place in the unit's view of the file system. Any bind mounts
created with this option are specific to the unit, and are not visible in the host's mount
table. This option expects a whitespace separated list of bind mount definitions. Each
definition consists of a colon-separated triple of source path, destination path and
option string, where the latter two are optional. If only a source path is specified the
source and destination is taken to be the same. The option string may be either "rbind" or
"norbind" for configuring a recursive or non-recursive bind mount. If the destination path
is omitted, the option string must be omitted too.

User
Set the UNIX user or group that the processes are executed as, respectively. Takes a
single user or group name, or a numeric ID as argument. For system services (services run
by the system service manager, i.e. managed by PID 1) and for user services of the root
user (services managed by root's instance of systemd --user), the default is "root", but
"User" may be used to specify a different user. For user services of any other user,
switching user identity is not permitted, hence the only valid setting is the same user
the user's service manager is running as. If no group is set, the default group of the
user is used. This setting does not affect commands whose command line is prefixed with
"+".

Note that restrictions on the user/group name syntax are enforced: the specified name must
consist only of the characters a-z, A-Z, 0-9, "_" and "-", except for the first character
which must be one of a-z, A-Z or "_" (i.e. numbers and "-" are not permitted as first
character). The user/group name must have at least one character, and at most 31. These
restrictions are enforced in order to avoid ambiguities and to ensure user/group names and
unit files remain portable among Linux systems.

When used in conjunction with "DynamicUser" the user/group name specified is dynamically
allocated at the time the service is started, and released at the time the service is
stopped X unless it is already allocated statically (see below). If "DynamicUser" is not
used the specified user and group must have been created statically in the user database
no later than the moment the service is started, for example using the sysusers.d(5)
facility, which is applied at boot or package install time. Optional. Type uniline.

Group
Set the UNIX user or group that the processes are executed as, respectively. Takes a
single user or group name, or a numeric ID as argument. For system services (services run
by the system service manager, i.e. managed by PID 1) and for user services of the root
user (services managed by root's instance of systemd --user), the default is "root", but
"User" may be used to specify a different user. For user services of any other user,
switching user identity is not permitted, hence the only valid setting is the same user
the user's service manager is running as. If no group is set, the default group of the
user is used. This setting does not affect commands whose command line is prefixed with
"+".

DynamicUser
Takes a boolean parameter. If set, a UNIX user and group pair is allocated dynamically
when the unit is started, and released as soon as it is stopped. The user and group will
not be added to /etc/passwd or /etc/group, but are managed transiently during runtime. The
nss-systemd(8) glibc NSS module provides integration of these dynamic users/groups into
the system's user and group databases. The user and group name to use may be configured
via "User" and "Group" (see above). If these options are not used and dynamic user/group
allocation is enabled for a unit, the name of the dynamic user/group is implicitly derived
from the unit name. If the unit name without the type suffix qualifies as valid user name
it is used directly, otherwise a name incorporating a hash of it is used. If a statically
allocated user or group of the configured name already exists, it is used and no dynamic
user/group is allocated. Note that if "User" is specified and the static group with the
name exists, then it is required that the static user with the name already exists.
Similarly, if "Group" is specified and the static user with the name exists, then it is
required that the static group with the name already exists. Dynamic users/groups are
allocated from the UID/GID range 61184X65519. It is recommended to avoid this range for
regular system or login users. At any point in time each UID/GID from this range is only
assigned to zero or one dynamically allocated users/groups in use. However, UID/GIDs are
recycled after a unit is terminated. Care should be taken that any processes running as
part of a unit for which dynamic users/groups are enabled do not leave files or
directories owned by these users/groups around, as a different unit might get the same
UID/GID assigned later on, and thus gain access to these files or directories. If
"DynamicUser" is enabled, "RemoveIPC", "PrivateTmp" are implied. This ensures that the
lifetime of IPC objects and temporary files created by the executed processes is bound to
the runtime of the service, and hence the lifetime of the dynamic user/group. Since /tmp
and /var/tmp are usually the only world-writable directories on a system this ensures that
a unit making use of dynamic user/group allocation cannot leave files around after unit
termination. Moreover "ProtectSystem=strict" and "ProtectHome=read-only" are implied, thus
prohibiting the service to write to arbitrary file system locations. In order to allow the
service to write to certain directories, they have to be whitelisted using
"ReadWritePaths", but care must be taken so that UID/GID recycling doesn't create security
issues involving files created by the service. Use "RuntimeDirectory" (see below) in order
to assign a writable runtime directory to a service, owned by the dynamic user/group and
removed automatically when the unit is terminated. Use "StateDirectory", "CacheDirectory"
and "LogsDirectory" in order to assign a set of writable directories for specific purposes
to the service in a way that they are protected from vulnerabilities due to UID reuse (see
below). Defaults to off. Optional. Type boolean.

SupplementaryGroups
Sets the supplementary Unix groups the processes are executed as. This takes a space-
separated list of group names or IDs. This option may be specified more than once, in
which case all listed groups are set as supplementary groups. When the empty string is
assigned, the list of supplementary groups is reset, and all assignments prior to this one
will have no effect. In any way, this option does not override, but extends the list of
supplementary groups configured in the system group database for the user. This does not
affect commands prefixed with "+". Optional. Type list of uniline.

PAMName
Sets the PAM service name to set up a session as. If set, the executed process will be
registered as a PAM session under the specified service name. This is only useful in
conjunction with the "User" setting, and is otherwise ignored. If not set, no PAM session
will be opened for the executed processes. See pam(8) for details.

Note that for each unit making use of this option a PAM session handler process will be
maintained as part of the unit and stays around as long as the unit is active, to ensure
that appropriate actions can be taken when the unit and hence the PAM session terminates.
This process is named "(sd-pam)" and is an immediate child process of the unit's main
process.

Note that when this option is used for a unit it is very likely (depending on PAM
configuration) that the main unit process will be migrated to its own session scope unit
when it is activated. This process will hence be associated with two units: the unit it
was originally started from (and for which "PAMName" was configured), and the session
scope unit. Any child processes of that process will however be associated with the
session scope unit only. This has implications when used in combination with
"NotifyAccess""all", as these child processes will not be able to affect changes in the
original unit through notification messages. These messages will be considered belonging
to the session scope unit and not the original unit. It is hence not recommended to use
"PAMName" in combination with "NotifyAccess""all". Optional. Type uniline.

CapabilityBoundingSet
Controls which capabilities to include in the capability bounding set for the executed
process. See capabilities(7) for details. Takes a whitespace-separated list of capability
names, e.g. "CAP_SYS_ADMIN", "CAP_DAC_OVERRIDE", "CAP_SYS_PTRACE". Capabilities listed
will be included in the bounding set, all others are removed. If the list of capabilities
is prefixed with "~", all but the listed capabilities will be included, the effect of the
assignment inverted. Note that this option also affects the respective capabilities in the
effective, permitted and inheritable capability sets. If this option is not used, the
capability bounding set is not modified on process execution, hence no limits on the
capabilities of the process are enforced. This option may appear more than once, in which
case the bounding sets are merged by "AND", or by "OR" if the lines are prefixed with "~"
(see below). If the empty string is assigned to this option, the bounding set is reset to
the empty capability set, and all prior settings have no effect. If set to "~" (without
any further argument), the bounding set is reset to the full set of available
capabilities, also undoing any previous settings. This does not affect commands prefixed
with "+".

Example: if a unit has the following,

CapabilityBoundingSet=CAP_A CAP_B
CapabilityBoundingSet=CAP_B CAP_C

then "CAP_A", "CAP_B", and "CAP_C" are set. If the second line is prefixed with "~",
e.g.,

CapabilityBoundingSet=CAP_A CAP_B
CapabilityBoundingSet=~CAP_B CAP_C

then, only "CAP_A" is set. Optional. Type uniline.

AmbientCapabilities
Controls which capabilities to include in the ambient capability set for the executed
process. Takes a whitespace-separated list of capability names, e.g. "CAP_SYS_ADMIN",
"CAP_DAC_OVERRIDE", "CAP_SYS_PTRACE". This option may appear more than once in which case
the ambient capability sets are merged (see the above examples in
"CapabilityBoundingSet"). If the list of capabilities is prefixed with "~", all but the
listed capabilities will be included, the effect of the assignment inverted. If the empty
string is assigned to this option, the ambient capability set is reset to the empty
capability set, and all prior settings have no effect. If set to "~" (without any further
argument), the ambient capability set is reset to the full set of available capabilities,
also undoing any previous settings. Note that adding capabilities to ambient capability
set adds them to the process's inherited capability set.

Ambient capability sets are useful if you want to execute a process as a non-privileged
user but still want to give it some capabilities. Note that in this case option
"keep-caps" is automatically added to "SecureBits" to retain the capabilities over the
user change. "AmbientCapabilities" does not affect commands prefixed with "+". Optional.
Type uniline.

NoNewPrivileges
Takes a boolean argument. If true, ensures that the service process and all its children
can never gain new privileges through execve() (e.g. via setuid or setgid bits, or
filesystem capabilities). This is the simplest and most effective way to ensure that a
process and its children can never elevate privileges again. Defaults to false, but
certain settings force "NoNewPrivileges=yes", ignoring the value of this setting. This is
the case when "SystemCallFilter", "SystemCallArchitectures", "RestrictAddressFamilies",
"RestrictNamespaces", "PrivateDevices", "ProtectKernelTunables", "ProtectKernelModules",
"MemoryDenyWriteExecute", or "RestrictRealtime" are specified. Also see No New Privileges
Flag. Optional. Type boolean.

SecureBits
Controls the secure bits set for the executed process. Takes a space-separated combination
of options from the following list: "keep-caps", "keep-caps-locked", "no-setuid-fixup",
"no-setuid-fixup-locked", "noroot", and "noroot-locked". This option may appear more than
once, in which case the secure bits are ORed. If the empty string is assigned to this
option, the bits are reset to 0. This does not affect commands prefixed with "+". See
capabilities(7) for details. Optional. Type uniline.

SELinuxContext
Set the SELinux security context of the executed process. If set, this will override the
automated domain transition. However, the policy still needs to authorize the transition.
This directive is ignored if SELinux is disabled. If prefixed by "-", all errors will be
ignored. This does not affect commands prefixed with "+". See setexeccon(3) for details.
Optional. Type uniline.

AppArmorProfile
Takes a profile name as argument. The process executed by the unit will switch to this
profile when started. Profiles must already be loaded in the kernel, or the unit will
fail. This result in a non operation if AppArmor is not enabled. If prefixed by "-", all
errors will be ignored. This does not affect commands prefixed with "+". Optional. Type
uniline.

SmackProcessLabel
Takes a "SMACK64" security label as argument. The process executed by the unit will be
started under this label and SMACK will decide whether the process is allowed to run or
not, based on it. The process will continue to run under the label specified here unless
the executable has its own "SMACK64EXEC" label, in which case the process will transition
to run under that label. When not specified, the label that systemd is running under is
used. This directive is ignored if SMACK is disabled.

The value may be prefixed by "-", in which case all errors will be ignored. An empty value
may be specified to unset previous assignments. This does not affect commands prefixed
with "+". Optional. Type uniline.

LimitCPU
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

Note that most process resource limits configured with these options are per-process, and
processes may fork in order to acquire a new set of resources that are accounted
independently of the original process, and may thus escape limits set. Also note that
"LimitRSS" is not implemented on Linux, and setting it has no effect. Often it is
advisable to prefer the resource controls listed in systemd.resource-control(5) over these
per-process limits, as they apply to services as a whole, may be altered dynamically at
runtime, and are generally more expressive. For example, "MemoryLimit" is a more powerful
(and working) replacement for "LimitRSS".

For system units these resource limits may be chosen freely. For user units however (i.e.
units run by a per-user instance of systemd(1)), these limits are bound by (possibly more
restrictive) per-user limits enforced by the OS.

Resource limits not configured explicitly for a unit default to the value configured in
the various "DefaultLimitCPU", "DefaultLimitFSIZE", X options available in
systemd-system.conf(5), and X if not configured there X the kernel or per-user defaults,
as defined by the OS (the latter only for user services, see above). Optional. Type
uniline.

LimitFSIZE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitDATA
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitSTACK
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitCORE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitRSS
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitNOFILE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitAS
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitNPROC
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitMEMLOCK
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitLOCKS
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitSIGPENDING
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitMSGQUEUE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitNICE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitRTPRIO
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

LimitRTTIME
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for
details on the resource limit concept. Resource limits may be specified in two formats:
either as single value to set a specific soft and hard limit to the same value, or as
colon-separated pair "soft:hard" to set both limits individually (e.g. "LimitAS=4G:16G").
Use the string "infinity" to configure no limit on a specific resource. The multiplicative
suffixes K, M, G, T, P and E (to the base 1024) may be used for resource limits measured
in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time units
ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no
time unit is specified for "LimitCPU" the default unit of seconds is implied, while for
"LimitRTTIME" the default unit of microseconds is implied. Also, note that the effective
granularity of the limits might influence their enforcement. For example, time limits
specified for "LimitCPU" will be rounded up implicitly to multiples of 1s. For "LimitNICE"
the value may be specified in two syntaxes: if prefixed with "+" or "-", the value is
understood as regular Linux nice value in the range -20..19. If not prefixed like this the
value is understood as raw resource limit parameter in the range 0..40 (with 0 being
equivalent to 1).

UMask
Controls the file mode creation mask. Takes an access mode in octal notation. See umask(2)
for details. Defaults to 0022. Optional. Type uniline.

KeyringMode
Controls how the kernel session keyring is set up for the service (see session-keyring(7)
for details on the session keyring). Takes one of "inherit", "private", "shared". If set
to "inherit" no special keyring setup is done, and the kernel's default behaviour is
applied. If "private" is used a new session keyring is allocated when a service process is
invoked, and it is not linked up with any user keyring. This is the recommended setting
for system services, as this ensures that multiple services running under the same system
user ID (in particular the root user) do not share their key material among each other. If
"shared" is used a new session keyring is allocated as for "private", but the user keyring
of the user configured with "User" is linked into it, so that keys assigned to the user
may be requested by the unit's processes. In this modes multiple units running processes
under the same user ID may share key material. Unless "inherit" is selected the unique
invocation ID for the unit (see below) is added as a protected key by the name
"invocation_id" to the newly created session keyring. Defaults to "private" for the system
service manager and to "inherit" for the user service manager. Optional. Type enum.
choice: 'inherit', 'private', 'shared'.

OOMScoreAdjust
Sets the adjustment level for the Out-Of-Memory killer for executed processes. Takes an
integer between -1000 (to disable OOM killing for this process) and 1000 (to make killing
of this process under memory pressure very likely). See proc.txt for details. Optional.
Type integer.

TimerSlackNSec
Sets the timer slack in nanoseconds for the executed processes. The timer slack controls
the accuracy of wake-ups triggered by timers. See prctl(2) for more information. Note that
in contrast to most other time span definitions this parameter takes an integer value in
nano-seconds if no unit is specified. The usual time units are understood too. Optional.
Type uniline.

Personality
Controls which kernel architecture uname(2) shall report, when invoked by unit processes.
Takes one of the architecture identifiers "x86", "x86-64", "ppc", "ppc-le", "ppc64",
"ppc64-le", "s390" or "s390x". Which personality architectures are supported depends on
the system architecture. Usually the 64bit versions of the various system architectures
support their immediate 32bit personality architecture counterpart, but no others. For
example, "x86-64" systems support the "x86-64" and "x86" personalities but no others. The
personality feature is useful when running 32-bit services on a 64-bit host system. If not
specified, the personality is left unmodified and thus reflects the personality of the
host system's kernel. Optional. Type enum. choice: 'x86', 'x86-64', 'ppc', 'ppc-le',
'ppc64', 'ppc64-le', 's390', 's390x'.

IgnoreSIGPIPE
Takes a boolean argument. If true, causes "SIGPIPE" to be ignored in the executed process.
Defaults to true because "SIGPIPE" generally is useful only in shell pipelines. Optional.
Type boolean.

Nice
Sets the default nice level (scheduling priority) for executed processes. Takes an integer
between -20 (highest priority) and 19 (lowest priority). See setpriority(2) for details.
Optional. Type integer.

CPUSchedulingPolicy
Sets the CPU scheduling policy for executed processes. Takes one of "other", "batch",
"idle", "fifo" or "rr". See sched_setscheduler(2) for details. Optional. Type enum.
choice: 'other', 'batch', 'idle', 'fifo', 'rr'.

CPUSchedulingPriority
Sets the CPU scheduling priority for executed processes. The available priority range
depends on the selected CPU scheduling policy (see above). For real-time scheduling
policies an integer between 1 (lowest priority) and 99 (highest priority) can be used. See
sched_setscheduler(2) for details. Optional. Type uniline.

CPUSchedulingResetOnFork
Takes a boolean argument. If true, elevated CPU scheduling priorities and policies will be
reset when the executed processes fork, and can hence not leak into child processes. See
sched_setscheduler(2) for details. Defaults to false. Optional. Type boolean.

CPUAffinity
Controls the CPU affinity of the executed processes. Takes a list of CPU indices or ranges
separated by either whitespace or commas. CPU ranges are specified by the lower and upper
CPU indices separated by a dash. This option may be specified more than once, in which
case the specified CPU affinity masks are merged. If the empty string is assigned, the
mask is reset, all assignments prior to this will have no effect. See sched_setaffinity(2)
for details. Optional. Type list of uniline.

IOSchedulingClass
Sets the I/O scheduling class for executed processes. Takes an integer between 0 and 3 or
one of the strings "none", "realtime", "best-effort" or "idle". See ioprio_set(2) for
details. Optional. Type enum. choice: '0', '1', '2', '3', 'none', 'realtime',
'best-effort', 'idle'.

IOSchedulingPriority
Sets the I/O scheduling priority for executed processes. Takes an integer between 0
(highest priority) and 7 (lowest priority). The available priorities depend on the
selected I/O scheduling class (see above). See ioprio_set(2) for details. Optional. Type
integer.

ProtectSystem
Takes a boolean argument or the special values "full" or "strict". If true, mounts the
/usr and /boot directories read-only for processes invoked by this unit. If set to "full",
the /etc directory is mounted read-only, too. If set to "strict" the entire file system
hierarchy is mounted read-only, except for the API file system subtrees /dev, /proc and
/sys (protect these directories using "PrivateDevices", "ProtectKernelTunables",
"ProtectControlGroups"). This setting ensures that any modification of the vendor-supplied
operating system (and optionally its configuration, and local mounts) is prohibited for
the service. It is recommended to enable this setting for all long-running services,
unless they are involved with system updates or need to modify the operating system in
other ways. If this option is used, "ReadWritePaths" may be used to exclude specific
directories from being made read-only. This setting is implied if "DynamicUser" is set.
For this setting the same restrictions regarding mount propagation and privileges apply as
for "ReadOnlyPaths" and related calls, see below. Defaults to off. Optional. Type enum.
choice: 'no', 'yes', 'full', 'strict'.

ProtectHome
Takes a boolean argument or "read-only". If true, the directories /home, /root and
/run/user are made inaccessible and empty for processes invoked by this unit. If set to
"read-only", the three directories are made read-only instead. It is recommended to enable
this setting for all long-running services (in particular network-facing ones), to ensure
they cannot get access to private user data, unless the services actually require access
to the user's private data. This setting is implied if "DynamicUser" is set. For this
setting the same restrictions regarding mount propagation and privileges apply as for
"ReadOnlyPaths" and related calls, see below. Optional. Type enum. choice: 'no', 'yes',
'read-only'.

RuntimeDirectory
These options take a whitespace-separated list of directory names. The specified directory
names must be relative, and may not include "." or "..". If set, one or more directories
by the specified names will be created (including their parents) below /run (or
$XDG_RUNTIME_DIR for user services), /var/lib (or $XDG_CONFIG_HOME for user services),
/var/cache (or $XDG_CACHE_HOME for user services), /var/log (or $XDG_CONFIG_HOME/log for
user services), or /etc (or $XDG_CONFIG_HOME for user services), respectively, when the
unit is started.

In case of "RuntimeDirectory" the lowest subdirectories are removed when the unit is
stopped. It is possible to preserve the specified directories in this case if
"RuntimeDirectoryPreserve" is configured to "restart" or "yes" (see below). The
directories specified with "StateDirectory", "CacheDirectory", "LogsDirectory",
"ConfigurationDirectory" are not removed when the unit is stopped.

Except in case of "ConfigurationDirectory", the innermost specified directories will be
owned by the user and group specified in "User" and "Group". If the specified directories
already exist and their owning user or group do not match the configured ones, all files
and directories below the specified directories as well as the directories themselves will
have their file ownership recursively changed to match what is configured. As an
optimization, if the specified directories are already owned by the right user and group,
files and directories below of them are left as-is, even if they do not match what is
requested. The innermost specified directories will have their access mode adjusted to the
what is specified in "RuntimeDirectoryMode", "StateDirectoryMode", "CacheDirectoryMode",
"LogsDirectoryMode" and "ConfigurationDirectoryMode".

These options imply "BindPaths" for the specified paths. When combined with
"RootDirectory" or "RootImage" these paths always reside on the host and are mounted from
there into the unit's file system namespace.

If "DynamicUser" is used in conjunction with "StateDirectory", "CacheDirectory" and
"LogsDirectory" is slightly altered: the directories are created below /var/lib/private,
/var/cache/private and /var/log/private, respectively, which are host directories made
inaccessible to unprivileged users, which ensures that access to these directories cannot
be gained through dynamic user ID recycling. Symbolic links are created to hide this
difference in behaviour. Both from perspective of the host and from inside the unit, the
relevant directories hence always appear directly below /var/lib, /var/cache and /var/log.

Use "RuntimeDirectory" to manage one or more runtime directories for the unit and bind
their lifetime to the daemon runtime. This is particularly useful for unprivileged daemons
that cannot create runtime directories in /run due to lack of privileges, and to make sure
the runtime directory is cleaned up automatically after use. For runtime directories that
require more complex or different configuration or lifetime guarantees, please consider
using tmpfiles.d(5).